With Tennesee’s primary just four days away — Sen. Lamar Alexander, R-Tenn., is being challenged by conservative state Rep. Joe Carr for his U.S. Senate seat — author Brad Thor retweeted this flashback from March 19:

U.S. Sen. Lamar Alexander (R-TN) will appear with former Florida Gov. Jeb Bush (R) and Gov. Bill Haslam (R-TN) Wednesday at an education roundtable discussion sponsored by pro-Common Core Tennessee Chamber of Commerce and Industry and the Tennessee Business Roundtable.

Alexander’s campaign has been blasting out ads that declare he is against a “national school board”. Lucky for Alexander, no such de jure national school board technically exists. It’s easy to say you’re against something that doesn’t exist in law. Unlucky for Alexander, a de facto national school board does exist. Not only does a de facto national school board exist, but it also has a curriculum. Oh, Alexander has been the superintendent for decades.

What is this de facto national school board? It’s called the U.S. Department of Education and the Senate Education Committee. Its current curriculum? Common Core.

In recent months, Alexander has appeared alongside Governor Bill Haslam as a show of solidarity for Tennessee’s use of Common Core. But the standards are also a political liability in the current climate, even for someone like Alexander who is expected to have a fairly easy time keeping his seat.

“I always choose my words carefully,” Alexander said Monday – with a laugh – when asked if he was being careful how he talks about Common Core.